The PET Facilities Core will co-ordinate those aspects of the initial acquisition, reconstruction and archiving of the PET, clinical and CT data that are shared among the four projects. Dr. Powers will the Director of this Core. All PET studies will be done on the Siemens 961 ECAT EXACT HR 47 PET scanner located in the Neurocritical Care PET Research Facility in the Neurology Neurosurgery Intensive Care Unit. This facility is dedicated to scientific research with studies of a cute brain injury given top priority. it is outfitted with al the life support equipment available elsewhere in the NNICU. Currently, all oxygen-15 radiopharmaceuticals necessary for performance of the PET measurements are prepared in the Washington University Medical Center Cyclotron Facility staffed by trained operators from 0700-1700, Monday through Friday. In order to successfully recruit patients with acute traumatic brain injury for Projects 1 and 2, it will be necessary to expand working hours of the Neurocritical Care PET Research Facility outside the current working hours. In year 1, we will construct a delivery system from a Tandem Cascade Accelerlator currently operating in the Rast Building Imaging Center two blocks away. This system will provide the flexibility to study patients during off-hours without the need for a cyclotron operator. Each of the four projects involves acquisition and recording of clinical and diagnostic laboratory information on patients with traumatic brain injury and intracerebral hemorrhage. In our preliminary studies we have used data sheets filled out by hand for this purpose. During year 1, we will continue to use our paper data forms to collect data. This will allow us to gain experience with the data collection and modify the forms accordingly to improve accuracy and efficiency. These revised and modified forms will serve as the basis for modifications to an existing computerized database system to be carried out in year 2. Modification and implementation of this clinical database to serve th needs of this program project should provide improvement in the efficiency, standardization and integrity of data collection and retrieval.